Final answer:
Premiums are not an example of risk retention as they relate to payments made to insurance companies for coverage, contrasting with copayments, deductibles, and self-insurance which involve the insured retaining a portion of the risk.
Step-by-step explanation:
Among the provided options, all are examples of risk retention except for premiums. Risk retention involves the insured party bearing a part of the risk, which includes mechanisms like deductibles, copayments, and self-insurance. Deductibles are the out-of-pocket expenses before the insurer covers the rest, while co-payments are fixed amounts paid before receiving services. Self-insurance is when a company or individual sets aside money to cover potential losses. Unlike these, premiums are the regular payments made to insurance companies for the coverage, and do not represent the insured party retaining risk but rather transferring it.